Lighting, Light Fixtures, Ceiling and Exhaust Fans - Does recessed lighting cause a significant increase in energy cost?

I'm trying to figure out why my energy bill is consistently $25-40 more than my sister's who lives around the corner and runs her A/C every day for about an hour (I don't have A/C)...we do about the same amount of laundry, her stove is electric while mine is gas...the only real difference is our house is full of recessed lighting while her's only has a little...I know it is not enough info to go on but I guess all I really want to know is my original question :D

recessed lights do not neccesssarily lead to increased cooling or heating costs but they may. They produce heat just like any other light. If you have a lot of them and/or they are high wattage, they can cause increased cooling costs.

Just the same, if you do not have a sealed can, you can lose heat into the attic or if there is no insulation around the cans, this too can lead to heat loss via the attic. Note: only IC rated cans can be in direct contact with insulation.

Additioanally, if you use more lighting than she does then you are going to see increased electrical usage for lighting. This may or may not be offset by her use of the A/C.

Check your bills for actual usage and compare.

ou can also fiure out how much electricity just about anything uses if you know the wattage. Figure out what your total wattage for lighting is and run the numbers.

Unless you have tons of light, it does seem that your sis would be spending more on electricity than you though.